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Vedelago J, Geser FA, Muñoz ID, Stabilini A, Yukihara EG, Jaekel O. Assessment of secondary neutrons in particle therapy by Monte Carlo simulations. Phys Med Biol 2021; 67. [PMID: 34905742 DOI: 10.1088/1361-6560/ac431b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 12/14/2021] [Indexed: 11/12/2022]
Abstract
OBJECTIVE The purpose of this study is to estimate the energy and angular distribution of secondary neutrons inside a phantom in hadron therapy, which will support decisions on detector choice and experimental setup design for in-phantom secondary neutron measurements. APPROACH Dedicated Monte Carlo simulations were implemented, considering clinically relevant energies of protons, helium and carbon ions. Since scored quantities can vary from different radiation transport models, the codes FLUKA, TOPAS and MCNP were used. The geometry of an active scanning beam delivery system for heavy ion treatment was implemented, and simulations of pristine and spread-out Bragg peaks were carried out. Previous studies, focused on specific ion types or single energies, are qualitatively in agreement with the obtained results. MAIN RESULTS The secondary neutrons energy distributions present a continuous spectrum with two peaks, one centred on the thermal/epithermal region, and one on the high-energy region, with the most probable energy ranging from 19 MeV up to 240 MeV, depending on the ion type and its initial energy. The simulations show that the secondary neutron energies may exceed 400 MeV and, therefore, suitable neutron detectors for this energy range shall be needed. Additionally, the angular distribution of the low energy neutrons is quite isotropic, whereas the fast/relativistic neutrons are mainly scattered in the down-stream direction. SIGNIFICANCE It would be possible to minimize the influence of the heavy ions when measuring the neutron-generated recoil protons by selecting appropriate measurement positions within the phantom. Although there are discrepancies among the three Monte Carlo codes, the results agree qualitatively and in order of magnitude, being sufficient to support further investigations with the ultimate goal of mapping the secondary neutron doses both in- and out-of-field in hadrontherapy. The obtained secondary neutron spectra are available as supplementary material.
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Affiliation(s)
- José Vedelago
- German Cancer Research Centre, Im Neuenheimer Feld 280, Heidelberg, 69120, GERMANY
| | - Federico A Geser
- Paul Scherrer Institut, Forschungsstrasse 111, Villigen PSI, 5232, SWITZERLAND
| | - Iván D Muñoz
- German Cancer Research Centre, Im Neuenheimer Feld 280, Heidelberg, 69120, GERMANY
| | - Alberto Stabilini
- Paul Scherrer Institut, Forschungsstrasse 111, Villigen PSI, 5235, SWITZERLAND
| | - Eduardo G Yukihara
- Paul Scherrer Institut, Forschungsstrasse 111, Villigen PSI, 5232, SWITZERLAND
| | - Oliver Jaekel
- German Cancer Research Centre, Im Neuenheimer Feld 280, Heidelberg, 69120, GERMANY
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Bolzonella M, Caresana M, Ferrarini M, Babut R. Characterization of a novel passive personal fast neutron dosimeter based on a CR-39 track detector in monochromatic neutron fields via Monte Carlo simulations and experiments. RADIAT MEAS 2021. [DOI: 10.1016/j.radmeas.2021.106627] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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3
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Rabus H, Gómez-Ros JM, Villagrasa C, Eakins J, Vrba T, Blideanu V, Zankl M, Tanner R, Struelens L, Brkić H, Domingo C, Baiocco G, Caccia B, Huet C, Ferrari P. Quality assurance for the use of computational methods in dosimetry: activities of EURADOS Working Group 6 'Computational Dosimetry'. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2021; 41:46-58. [PMID: 33406511 DOI: 10.1088/1361-6498/abd914] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 01/06/2021] [Indexed: 06/12/2023]
Abstract
Working Group (WG) 6 'Computational Dosimetry' of the European Radiation Dosimetry Group promotes good practice in the application of computational methods for radiation dosimetry in radiation protection and the medical use of ionising radiation. Its cross-sectional activities within the association cover a large range of current topics in radiation dosimetry, including more fundamental studies of radiation effects in complex systems. In addition, WG 6 also performs scientific research and development as well as knowledge transfer activities, such as training courses. Monte Carlo techniques, including the use of anthropomorphic and other numerical phantoms based on voxelised geometrical models, play a strong part in the activities pursued in WG 6. However, other aspects and techniques, such as neutron spectra unfolding, have an important role as well. A number of intercomparison exercises have been carried out in the past to provide information on the accuracy with which computational methods are applied and whether best practice is being followed. Within the exercises that are still ongoing, the focus has changed towards assessing the uncertainty that can be achieved with these computational methods. Furthermore, the future strategy of WG 6 also includes an extension of the scope toward experimental benchmark activities and evaluation of cross-sections and algorithms, with the vision of establishing a gold standard for Monte Carlo methods used in medical and radiobiological applications.
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Affiliation(s)
- H Rabus
- Physikalisch-Technische Bundesanstalt (PTB), Abbestrasse 2-12, 10587 Berlin, Germany
| | - J M Gómez-Ros
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
| | - C Villagrasa
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay-aux-Roses, France
| | - J Eakins
- Public Health England (PHE), Didcot, United Kingdom
| | - T Vrba
- Czech Technical University in Prague (CTU), Prague, Czech Republic
| | - V Blideanu
- Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA), Saclay, France
| | - M Zankl
- Helmholtz Zentrum München German Research Center for Environmental Health (HMGU), Neuherberg, Germany
| | - R Tanner
- Public Health England (PHE), Didcot, United Kingdom
| | - L Struelens
- Belgian Nuclear Research Center (SCK·CEN), Mol, Belgium
| | - H Brkić
- J. J. Strossmayer University of Osijek (MEFOS), Osijek, Croatia
| | - C Domingo
- Universitat Autonoma de Barcelona (UAB), Barcelona, Spain
| | - G Baiocco
- Physics Department, University of Pavia, Pavia, Italy
| | - B Caccia
- National Institute of Health (ISS), Rome, Italy
| | - C Huet
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay-aux-Roses, France
| | - P Ferrari
- National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Bologna, Italy
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Carnicer A, Angellier G, Hofverberg P, Bergerot JM, Gerard A, Peucelle C, Vidal M, Hérault J. Study of the responses and calibration procedures of neutron and gamma area and environmental detectors for use in proton therapy. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2019; 39:250-278. [PMID: 30721148 DOI: 10.1088/1361-6498/aaf437] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Ambient dose equivalent measurements with radiation protection instruments are associated to large uncertainties, mostly due to the energy dependence of the instrument response and to the dissimilarity between the spectra of the standard calibration source and the workplace field. The purpose of this work is to evaluate its impact on the performance of area and environmental detectors in the proton therapy environment, and to provide practical solutions whenever needed and possible. The study was carried out at the Centre Antoine Lacassagne (CAL) proton therapy site, and included a number of commercially available area detectors and a home-made environmental thermoluminescent dosimeter based on a polyethylene moderator loaded with TLD600H/TLD700H pairs. Monte Carlo simulations were performed with MCNP to calculate, first, missing or partially lacking instrument responses, covering the range of energies involved in proton therapy. Second, neutron and gamma spectra were computed at selected positions in and outside the CAL proton therapy bunkers. Appropriate correction factors were then derived for each detector, workplace location and calibration radionuclide source, which amounts to up to 1.9 and 1.5 for neutron and photon area detectors, respectively, and suggest that common ambient dose equivalent instruments might not meet IEC requirements. The TLD environmental system was calibrated in situ and appropriate correction factors were applied to account for the cosmic spectra. Measurements performed with this system from 2014 to 2017 around the installation were consistent with reference natural background dose data and with pre-operational levels registered at the site before the construction of the building in 1988, showing thus no contribution from the site clinical activities. An in situ verification procedure for the radiation protection instruments was also implemented in 2016 at the low energy treatment room using the QA beam reference conditions. The method presents main methodological, practical and economic advantages over external verifications.
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Affiliation(s)
- Adela Carnicer
- Centre Antoine Lacassagne (CAL), 227 avenue de la Lanterne, 06200 Nice, France. Fédération Claude Lalanne-Université Côte d'Azur, France
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Mares V, Trinkl S, Iwamoto Y, Masuda A, Matsumoto T, Hagiwara M, Satoh D, Yashima H, Shima T, Nakamura T. Neutron spectrometry and dosimetry in 100 and 300 MeV quasi-mono-energetic neutron field at RCNP, Osaka University, Japan. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201715308020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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6
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Goldhagen P. An Extended-Range Multisphere Neutron Spectrometer with High Sensitivity and Improved Resolution. NUCL TECHNOL 2017. [DOI: 10.13182/nt11-a12274] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Paul Goldhagen
- U.S. Department of Homeland Security National Urban Security Technology Laboratory201 Varick Street, New York, New York 10014-7447
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Infantino A, Cicoria G, Lucconi G, Pancaldi D, Vichi S, Zagni F, Mostacci D, Marengo M. Radiation Protection Studies for Medical Particle Accelerators using Fluka Monte Carlo Code. RADIATION PROTECTION DOSIMETRY 2017; 173:185-191. [PMID: 27886990 DOI: 10.1093/rpd/ncw302] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Radiation protection (RP) in the use of medical cyclotrons involves many aspects both in the routine use and for the decommissioning of a site. Guidelines for site planning and installation, as well as for RP assessment, are given in international documents; however, the latter typically offer analytic methods of calculation of shielding and materials activation, in approximate or idealised geometry set-ups. The availability of Monte Carlo (MC) codes with accurate up-to-date libraries for transport and interaction of neutrons and charged particles at energies below 250 MeV, together with the continuously increasing power of modern computers, makes the systematic use of simulations with realistic geometries possible, yielding equipment and site-specific evaluation of the source terms, shielding requirements and all quantities relevant to RP at the same time. In this work, the well-known FLUKA MC code was used to simulate different aspects of RP in the use of biomedical accelerators, particularly for the production of medical radioisotopes. In the context of the Young Professionals Award, held at the IRPA 14 conference, only a part of the complete work is presented. In particular, the simulation of the GE PETtrace cyclotron (16.5 MeV) installed at S. Orsola-Malpighi University Hospital evaluated the effective dose distribution around the equipment; the effective number of neutrons produced per incident proton and their spectral distribution; the activation of the structure of the cyclotron and the vault walls; the activation of the ambient air, in particular the production of 41Ar. The simulations were validated, in terms of physical and transport parameters to be used at the energy range of interest, through an extensive measurement campaign of the neutron environmental dose equivalent using a rem-counter and TLD dosemeters. The validated model was then used in the design and the licensing request of a new Positron Emission Tomography facility.
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Affiliation(s)
- Angelo Infantino
- Department of Industrial Engineering, Laboratory of Montecuccolino, University of Bologna, Via dei Colli 16, 40136 Bologna, Italy
| | - Gianfranco Cicoria
- Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy
| | - Giulia Lucconi
- Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy
| | - Davide Pancaldi
- Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy
| | - Sara Vichi
- Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy
| | - Federico Zagni
- Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy
| | - Domiziano Mostacci
- Department of Industrial Engineering, Laboratory of Montecuccolino, University of Bologna, Via dei Colli 16, 40136 Bologna, Italy
| | - Mario Marengo
- Medical Physics Department, S. Orsola-Malpighi University Hospital, Via Massarenti 9, 40138 Bologna, Italy
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De Smet V, De Saint-Hubert M, Dinar N, Manessi GP, Aza E, Cassell C, Saldarriaga Vargas C, Van Hoey O, Mathot G, Stichelbaut F, De Lentdecker G, Gerardy I, Silari M, Vanhavere F. Secondary neutrons inside a proton therapy facility: MCNPX simulations compared to measurements performed with a Bonner Sphere Spectrometer and neutron H*(10) monitors. RADIAT MEAS 2017. [DOI: 10.1016/j.radmeas.2017.03.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Sokolov A, Fehrenbacher G, Radon T. DESIGN DEVELOPMENT OF A PASSIVE NEUTRON DOSEMETER FOR THE USE AT HIGH-ENERGY ACCELERATORS. RADIATION PROTECTION DOSIMETRY 2016; 170:195-198. [PMID: 26628610 DOI: 10.1093/rpd/ncv489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/23/2015] [Indexed: 06/05/2023]
Abstract
For the radiation survey at intermediate and high-energy accelerators, there is a need for a neutron dosemeter which provides reliable readings of the neutron dose in a wide energy range for continuous and pulsed radiation. The objective of this development is to find a dosemeter that fulfils the necessary requirements and can be reliably used to prove that the radiation levels in areas around accelerators are in accordance with the limits of the respective radiation protection legislation. A simple layout with small dimensions and light weight as well as the usage of common materials to lower the production costs is to be achieved.
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Lee KW, Sheu RJ. Spectral correction factors for conventional neutron dosemeters used in high-energy neutron environments. RADIATION PROTECTION DOSIMETRY 2015; 164:210-218. [PMID: 25280480 DOI: 10.1093/rpd/ncu298] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 09/03/2014] [Indexed: 06/03/2023]
Abstract
High-energy neutrons (>10 MeV) contribute substantially to the dose fraction but result in only a small or negligible response in most conventional moderated-type neutron detectors. Neutron dosemeters used for radiation protection purpose are commonly calibrated with (252)Cf neutron sources and are used in various workplace. A workplace-specific correction factor is suggested. In this study, the effect of the neutron spectrum on the accuracy of dose measurements was investigated. A set of neutron spectra representing various neutron environments was selected to study the dose responses of a series of Bonner spheres, including standard and extended-range spheres. By comparing (252)Cf-calibrated dose responses with reference values based on fluence-to-dose conversion coefficients, this paper presents recommendations for neutron field characterisation and appropriate correction factors for responses of conventional neutron dosemeters used in environments with high-energy neutrons. The correction depends on the estimated percentage of high-energy neutrons in the spectrum or the ratio between the measured responses of two Bonner spheres (the 4P6_8 extended-range sphere versus the 6″ standard sphere).
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Affiliation(s)
- K W Lee
- Institute of Nuclear Engineering and Science, National Tsing Hua University, 101 Sec. 2, Kung Fu Road, Hsinchu 300, Taiwan, R.O.C. Institute of Nuclear Energy Research, Lungtan, Taoyuan, Taiwan, R.O.C
| | - R J Sheu
- Institute of Nuclear Engineering and Science, National Tsing Hua University, 101 Sec. 2, Kung Fu Road, Hsinchu 300, Taiwan, R.O.C. Department of Engineering and System Science, National Tsing Hua University, 101 Sec. 2, Kung Fu Road, Hsinchu 300, Taiwan, R.O.C.
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Rühm W, Mares V, Pioch C, Agosteo S, Endo A, Ferrarini M, Rakhno I, Rollet S, Satoh D, Vincke H. Comparison of Bonner sphere responses calculated by different Monte Carlo codes at energies between 1 MeV and 1 GeV – Potential impact on neutron dosimetry at energies higher than 20 MeV. RADIAT MEAS 2014. [DOI: 10.1016/j.radmeas.2014.05.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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12
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Zhu Q, Song F, Ren J, Chen X, Zhou B. The criteria for selecting a method for unfolding neutron spectra based on the information entropy theory. RADIAT MEAS 2014. [DOI: 10.1016/j.radmeas.2013.12.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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13
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Bedogni R. Neutron spectrometry with Bonner Spheres for area monitoring in particle accelerators. RADIATION PROTECTION DOSIMETRY 2011; 146:383-394. [PMID: 21653582 DOI: 10.1093/rpd/ncr238] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Selecting the instruments to determine the operational quantities in the neutron fields produced by particle accelerators involves a combination of aspects, which is peculiar to these environments: the energy distribution of the neutron field, the continuous or pulsed time structure of the beam, the presence of other radiations to which the neutron instruments could have significant response and the large variability in the dose rate, which can be observed when moving from areas near the beam line to free-access areas. The use of spectrometric techniques in support of traditional instruments is highly recommended to improve the accuracy of dosimetric evaluations. The multi-sphere or Bonner Sphere Spectrometer (BSS) is certainly the most used device, due to characteristics such as the wide energy range, large variety of active and passive detectors suited for different workplaces, good photon discrimination and the simple signal management. Disadvantages are the poor energy resolution, weight and need to sequentially irradiate the spheres, leading to usually long measurement sessions. Moreover, complex unfolding analyses are needed to obtain the neutron spectra. This work is an overview of the BSS for area monitoring in particle accelerators.
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Affiliation(s)
- Roberto Bedogni
- INFN-LNF Frascati National Laboratories, Via E. Fermi n. 40-00044, Frascati (RM), Italy.
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Schuhmacher H. Workplace monitoring of mixed neutron-photon radiation fields and its contribution to external dosimetry. RADIATION PROTECTION DOSIMETRY 2011; 144:599-604. [PMID: 21285111 DOI: 10.1093/rpd/ncq588] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Workplace monitoring is a common procedure for determining measures for routine radiation protection in a particular working environment. For mixed radiation fields consisting of neutrons and photons, it is of increased importance because it contributes to the improved accuracy of individual monitoring. An example is the determination of field-specific correction factors, which can be applied to the readings of personal dosemeters. This paper explains the general problems associated with individual dosimetry of neutron radiation, and describes the various options for workplace monitoring. These options cover a range from the elaborate field characterisation using transport calculations or spectrometers to the simpler approach using area monitors. Examples are given for workplaces in nuclear industry, at particle accelerators and at flight altitudes.
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Affiliation(s)
- Helmut Schuhmacher
- Department 6.5, Physikalisch-Technische Bundesanstalt, 38116 Braunschweig, Germany.
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Garny S, Mares V, Roos H, Wagner F, Rühm W. Measurement of neutron spectra and neutron doses at the Munich FRM II therapy beam with Bonner spheres. RADIAT MEAS 2011. [DOI: 10.1016/j.radmeas.2010.08.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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16
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Hohmann E, Fehrenbacher G, Khurana S, Radon T, Reginatto M, Schardt D, Schuhmacher H, Wiegel B. The simulated workplace field with a high-energy neutron component produced by irradiating a Fe-target with 200 MeV/u 12C-ions. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2010.06.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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17
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Pioch C, Mares V, Rühm W. Influence of Bonner sphere response functions above 20 MeV on unfolded neutron spectra and doses. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2010.05.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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19
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Rühm W, Wallner A, Cullings H, Egbert SD, El-Faramawy N, Faestermann T, Kaul D, Knie K, Korschinek G, Nakamura N, Roberts J, Rugel G. 41Ca in Tooth Enamel. Part II: A Means for Retrospective Biological Neutron Dosimetry in Atomic Bomb Survivors. Radiat Res 2010; 174:146-54. [DOI: 10.1667/rr2044.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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20
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Iterative unfolding for Bonner sphere spectrometers using the MSANDB code – Sensitivity analysis and dose calculation. RADIAT MEAS 2010. [DOI: 10.1016/j.radmeas.2009.03.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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21
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Rollet S, Beck P, Latocha M, Wind M, Zechner A, Taylor GC. TEPC Measurements and Monte Carlo Calculations for Evaluating Ambient Dose Equivalent Response in Mixed Radiation Fields around the Shielded Area of a Carbon Ion Accelerator. NUCL TECHNOL 2009. [DOI: 10.13182/nt09-a9110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- S. Rollet
- Austrian Institute of Technology GmbH, A-2444 Seibersdorf, Austria
| | - P. Beck
- Austrian Institute of Technology GmbH, A-2444 Seibersdorf, Austria
| | - M. Latocha
- Austrian Institute of Technology GmbH, A-2444 Seibersdorf, Austria
| | - M. Wind
- Austrian Institute of Technology GmbH, A-2444 Seibersdorf, Austria
| | - A. Zechner
- Austrian Institute of Technology GmbH, A-2444 Seibersdorf, Austria
| | - G. C. Taylor
- National Physical Laboratory, Teddington TW11 0LW, United Kingdom
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Intercomparison of radiation protection devices in a high-energy stray neutron field, Part I: Monte Carlo simulations. RADIAT MEAS 2009. [DOI: 10.1016/j.radmeas.2009.03.029] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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23
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Intercomparison of radiation protection devices in a high-energy stray neutron field. Part III: Instrument response. RADIAT MEAS 2009. [DOI: 10.1016/j.radmeas.2009.05.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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24
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Reginatto M. What can we learn about the spectrum of high-energy stray neutron fields from Bonner sphere measurements? RADIAT MEAS 2009. [DOI: 10.1016/j.radmeas.2009.04.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Rühm W, Mares V, Pioch C, Weitzenegger E, Vockenroth R, Paretzke HG. Measurements of secondary neutrons from cosmic radiation with a Bonner sphere spectrometer at 79 degrees N. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2009; 48:125-133. [PMID: 19247682 DOI: 10.1007/s00411-009-0219-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Accepted: 02/09/2009] [Indexed: 05/27/2023]
Abstract
Air crew members and airline passengers are continuously exposed to cosmic radiation during their flights. Particles ejected by the sun during so-called solar particle events (SPEs) in periods of high solar activity can contribute to this exposure. In rare cases the dose from a single SPE might even exceed the annual dose limit of 1 mSv above which dose monitoring of air crews is legally required in Germany. Measurements performed by means of neutron monitors have already shown that the relative intensity of secondary neutrons from cosmic radiation is enhanced during an SPE, particularly at regions close to the magnetic poles of the Earth where shielding of the cosmic radiation by the geomagnetic field is low. Here we describe a Bonner sphere spectrometer installed at the Koldewey station at 79 degrees N, i.e. about 1,000 km from the geographic North pole, which is designed to provide first experimental data on the time-dependent energy spectrum of neutrons produced in the atmosphere during an SPE. This will be important to calculate doses from these neutrons to air crew members. The system is described in detail and first results are shown that were obtained during quiet periods of sun activity.
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Affiliation(s)
- Werner Rühm
- Helmholtz Zentrum München, National Research Center for Environmental Health, Institute of Radiation Protection, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany.
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